1. Field of the Invention
The present invention relates generally to heat exchanger assemblies. More particularly, the present invention relates to a manifold assembly for a heat exchanger for an automotive vehicle.
2. Disclosure Information
A typical automotive heat exchanger such as a radiator, includes a manifold assembly which conducts fluid flow through a plurality of flow tubes to reduce the operating temperature of the vehicle as is well known in the art. A manifold typically includes a tank member and a header member joined together. Various solderless tank-to-header joint arrangements have been proposed such as shown in British Patent No. 699,032. In these prior art arrangements, portions of the edges of the headers or associated separate clips formed on the headers are crimped onto flanges formed on the respective tanks to compress an o-ring or other shaped resilient gasket between the tank and the header. Typically, the headers are formed of a lighter gauge metal than the tanks or the tanks are formed of a suitable plastic with heavy gauge headers.
Numerous quality problems can be associated with the crimping process, such as shearing of the tabs on the header, failure to fully close the tabs resulting in leaks or a low burst strength of the manifold, or cracking the plastic tank and pinching or cutting the rubber o-ring. Furthermore, there are also design issues related to automotive radiators with plastic tanks. These include crevice corrosion under the o-ring, relaxation of the o-ring and cracking of the plastic tank caused by fatigue or calcium chloride attack. Because of these disadvantages, it would be desirable to build an all aluminum automotive radiator including a tank manufactured from an aluminum or aluminum alloy which would overcome the problems associated with the mechanical assembling of the tank-to-header joint.
Other automotive heat exchangers, such as heater cores, can also be manufactured from an aluminum alloy. However, the tank-to-header joint used on heater cores is primarily unsatisfactory due to assembly reasons. The heater core tank-to-header joint does not provide sufficient lead-in nor clearance for assembly of the tank to the header. Misaligned or improperly seated tanks can result in leaks after a brazing operation. A cam trimming operation in the stamping die must also be used on some tanks in order to assure a leak-free design. Therefore, it would be advantageous to provide a tank-to-header joint design which overcomes the problems associated with the prior art.
It is an object of the present invention to provide an all aluminum or aluminum alloy heat exchanger wherein the tank-to-header joint eliminates the problems inherent with the mechanical crimping or assembling as known in the prior art.